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IceAlisa
06-05-2011, 02:36 AM
I second the request. My heart made a jump when I saw the thread title but the excitement was cooled considerably. While this is an important step, the thread title is rather sensationalistic IMO.

agalisgv
06-06-2011, 04:05 AM
Methinks some are confusing a cure with something being mass marketed. It was big news when a polio vaccine was discovered, but it took several years before it was made widely available. Didn't negate the importance of the initial vaccine discovery though.

Wrt viral mutations, there are already different viral types of HIV. Mon can correct me if I'm wrong, but I believe this cure is for Hiv-1.

IceAlisa
06-06-2011, 04:08 AM
I wouldn't say the discovery of the vaccine is the same as this case. What happened here is a first step in a long road toward a cure for HIV. This isn't about making it widely available as it wouldn't be effective with a great number, if not the majority of HIV patients. It's about developing this to be safe and effective for most. And that is problematic at this point for several reasons, distribution just being one of them. Not so with the polio vaccine.

Do you honestly think that I, for instance who worked in medical research for years, would be confusing mass availability with a cure? Other posters who find the thread title problematic seem to be very competent on the topic as well. Far more competent than the OP, in fact. :shuffle:

It appears that it is you, agalisgv who do not understand the nature of this case and missed the part in your link that stated this is not a cure for the rest of the world. This is a very specific case, as stated previously. You also quote a process of development of gene editing that is currently in its beginning stages. Biomedical research is a very long road and we are not at the finish line yet.

Once it goes through all the stages of clinical trials and passes muster in all the usual ways, then we can talk about a cure and only then, mass distribution. What we have now is a case study where n=1.

agalisgv
06-06-2011, 04:45 AM
Do you honestly think that I, for instance who worked in medical research for years, would be confusing mass availability with a cure? yes

And frankly I'm tired of you ruining threads with your personal obsession with me. Get over it and stfu.

IceAlisa
06-06-2011, 04:49 AM
You need to chill.

And realize that I may have interest in the topic and not in you and also that other posters who understand this topic better than you, happen to agree that calling this thread "HIV cure found" is premature.

Seems to me you have a real problem admitting that you are wrong and lash out at people who point out that you could be wrong. You don't understand how biomedical research works and you've demonstrated this many a time. That's OK. It's impossible to understand everything just from Googling a few things. A little humility, please.

agalisgv
06-06-2011, 05:05 AM
I know you like to portray yourself as a medical expert, but I've found your knowledge base to be so consistently lacking, I don't even bother anymore.

Your constant attempts to post passive-aggressive barbs in response to me borders on pathological, so I will reiterate one last time, stop derailing the thread and stfu.

Kthnxbi

IceAlisa
06-06-2011, 05:17 AM
I know you like to portray yourself as a medical expert, but I've found your knowledge base to be so consistently lacking, I don't even bother anymore. You can hardly judge anyone's knowledge of that area having so little to none of it yourself.


Your constant attempts to post passive-aggressive barbs in response to me borders on pathological, so I will reiterate one last time, stop derailing the thread and stfu.

Kthnxbi
I was not derailing the thread, only trying to point out that why the thread title is inappropriate. It really did do a number on me when I first read it--I was about to start calling people and then I read the article.

Instead of being immature, perhaps you could provide an argument why this is considered a cure and not a principle that could make the scientists cautiously optimistic.

Anita18
06-06-2011, 07:12 AM
And realize that I may have interest in the topic and not in you and also that other posters who understand this topic better than you, happen to agree that calling this thread "HIV cure found" is premature.
To be fair, when I read about a cure for HIV or cancer on a figure skating (or anything else non-science related) forum BEFORE seeing it posted on say, Nature News's Twitter, I always think it's premature. :shuffle:

There was a similar thread in another forum I frequent a number of years ago regarding some kind of HIV vaccine discovered in a Chinese lab. The article went into good detail about how they made it, using the virus's DNA. I immediately shot down the hopes and dreams of many when I pointed out that HIV does not contain DNA. I did something similar just a few weeks ago on the same forum when someone made a thread about the cure for cancer. :P

Honestly, I had the same kneejerk "not this crap again" reaction when I saw the thread title, but when I saw that agalisgv had made it, I figured there must be SOMETHING truthful about it. And there is, but it's still a little sensationalistic. Maybe it's a case of the boy crying wolf for me.

IceAlisa
06-06-2011, 08:06 AM
Right, because HIV is a retrovirus and has RNA. I think I would be immediately skeptical about a cancer cure headline because there are so many and are so different that I can't imagine the same cure for all of them.

Quintuple
06-06-2011, 08:21 AM
So ...

Here's the thing ...

Amongst other tests administered before starting medication (i.e. type and subtype are automatic in an HIV test, but tropism and resistance assays are not), is a Trofile Assay, which is used to determine the particular tropsim of a person's virus. So, type (HIV-1 and HIV-2) does determine to a degree treatment possibilities, but not really since most people have HIV-1. Sub-type ... you can read about it here:

http://en.wikipedia.org/wiki/Subtypes_of_HIV

But mostly, resistance tests are given before medication is prescribed. I always get the two mixed up, but there's phenotyping and genotyping - one runs the resistance patterns across classes of drugs in general, and the other tests a person's strain against each drug one at a time. This determines what would be the best combination of medication across classes, depending if an infected person has key mutations (resistance) against a drug. In a really general sense ... as time goes on and people don't adhere to regimens, eventually experience treatment failure, and infect other people, we need more and more drugs across classes with different key mutation resistance profiles to "keep ahead" of the disease.

The newest class of drug is the Entry/(Fusion) inhibitor. So far, the only ones on the market are Selzentry and Fuzeon. Basically, each class of drugs attacks HIV during a different phase of cell takeover and replication.

In order to determine if one is eligible for this class of drugs, a Trofile Assay is administered. This determines the tropism ... err ... if one has a CCR5-d32 strain, a CXCR4 strain (rarer), or mixed-tropism. What this means is that the entry paths into the cell are either an R5 or X4 receptor. So far, entry inhibitors can only block CCR5 pathways. That's where this "cure" comes in. The whole thing you hear about Black Plague -resistant ancestors having an "immunity" to HIV are that R5 receptors are naturally blocked or mutated, so that if a person got infected with the more common R5 tropism, one would be "immune". It's a rare genetic mutation, but it still isn't a 100% guarantee of immunity either.

Aaaanyway, entry inhibitors so far only block R5 receptors. So if Tropism Assay shows that a person has X4-dominant virus or mixed tropism, the drug wouldn't help at all: the virus would still be able to attack cells.

Here's the problem with this whole cure: Tropism can change. One can show test results that show CCR5 tropism, therefore making the drug effective, but apparently, there's only so much micro-detection a test can do (i.e. "undetectable" HIV viral load is actually just <20 per mL). This means that most people probably do have mixed-tropism HIV, but it's just more common for the X4 tropic virus to be far less in proportion. So if a drug is used to eliminate the productivity of the R5 tropic virus ... the X4 tropic virus slowly takes over, and tropism "switches".

This is all hypothesis (i.e. the drugs have not been on the market long enough for definitive long-term tracking), but unless there becomes available, say, two drugs in the entry inhibitor class, one that targets CCR5 receptors and another that targets CXCR4 receptors, a long-term medication solution isn't currently possible. Just like with other class-combos in HIV medication: the selection pressure for the the few drug-resistant viruses becomes stronger, so a person eventually becomes resistant to an entire medication.

Argh, I know I just wrote that all in the most convoluted way possible, but the takeaway here is that unless a person has total blood transfusion or something, there's no guarantee that just mutating the CCR5 receptors completely renders the virus incapable of replication. So far, we can't target specific organ reservoirs of dormant virus, or completely guarantee that every single virus in a person's body is of a single tropism; so while the math can figure to be a "functional" cure (i.e. the time it would take a tropism to completely switch would be longer than a person's life expectancy when not on medication, for example), ... it needs a lot of work before becoming a true cure.

Sorry, too many articles I've read on these subjects, and you know that you get a different story each time.

agalisgv
06-06-2011, 09:22 AM
Thanks for that Quintuple. Here was something I read about the Berlin case that I think touches on some of your points.
The cells lacked the most common doorway, CCR5, that HIV needs to infect cells. But people with long-term HIV infection usually carry HIV capable of using another doorway called CXCR4. And tests showed that the Berlin patient's blood carried HIV like this. Moreover, tests also showed that the donor cells were susceptible to infection via the CXCR4 pathway.

Even so, the Berlin patient mysteriously remains HIV free.http://www.webmd.com/hiv-aids/news/20101215/hiv-aids-cure-faq?page=3

agalisgv
06-06-2011, 09:28 AM
Some more research involving clinical trials:
Zaia's team is exploring the use of taking a patient's own cells and genetically engineering them to fight HIV. The first studies are being done on patients with HIV lymphoma, who already require chemotherapy. Four patients already have been treated with low doses of genetically modified cells -- and the good news is that the modified cells can survive and expand for at least two years. From same article as above.

Cyn
06-06-2011, 01:23 PM
You need to chill.

And realize that I may have interest in the topic and not in you and also that other posters who understand this topic better than you, happen to agree that calling this thread "HIV cure found" is premature.

Seems to me you have a real problem admitting that you are wrong and lash out at people who point out that you could be wrong. You don't understand how biomedical research works and you've demonstrated this many a time. That's OK. It's impossible to understand everything just from Googling a few things. A little humility, please.

:respec: :respec: :respec:


I know you like to portray yourself as a medical expert, but I've found your knowledge base to be so consistently lacking, I don't even bother anymore.

Your constant attempts to post passive-aggressive barbs in response to me borders on pathological, so I will reiterate one last time, stop derailing the thread and stfu.

Kthnxbi

Jesus H. Christ, coming from you, that's beyond laughable. You post and post and post on subjects acting like you're some self-professed expert on every topic under the sun, and like I've said before, you treat this board, especially PI, like it's your own personal debate pulpit. I don't know if it's your personality type, but you absolutely crave validation and adoration, and since you slimed your way onto this board with a minimal interest in Figure Skating, that's been your M.O.

You behave here as though you are *never* wrong, and will post the most obscure and biased sources from Google-itis to "prove" that you're correct and anyone who disagrees with you is either misinformed, a fool, or an idiot. You need to try looking in a mirror sometime, because that's how you come off a lot of the time.

If IcaAlisa annoys you so damned much, put her on ignore, rather than telling her to STFU.

IceAlisa
06-06-2011, 04:43 PM
So ...

Here's the thing ...


Argh, I know I just wrote that all in the most convoluted way possible, but the takeaway here is that unless a person has total blood transfusion or something, there's no guarantee that just mutating the CCR5 receptors completely renders the virus incapable of replication. So far, we can't target specific organ reservoirs of dormant virus, or completely guarantee that every single virus in a person's body is of a single tropism; so while the math can figure to be a "functional" cure (i.e. the time it would take a tropism to completely switch would be longer than a person's life expectancy when not on medication, for example), ... it needs a lot of work before becoming a true cure.

Sorry, too many articles I've read on these subjects, and you know that you get a different story each time.

So what you are saying that the patient from the Bay Area in question could harbor virus of a different tropism that is currently dormant and is below detectable levels but theoretically (hopefully not!!!) could become active at some point and raise the viral loads again, leading to a new infection?

NancyNC
06-06-2011, 05:44 PM
I just hope that this can serve the anti-stem cell people a nice hot cup of STFU.

Not to seem redundant ;), but ITA!

And ETA that since I currently work in HIV research I was shocked to see that a cure had been found. ;)